A retired former partner at a well-known business law firm with offices in Utah and Nevada has had a rough go of it after he stopped taking his medication, his lawyer says.

David Alan Anderson, 60, got into a dispute with a fellow passenger Sunday over the attorney’s “claim” to an airplane armrest and is now jailed in federal custody pending a psychiatric evaluation after allegedly threatening arresting officers, according to the Deseret News.

After a knife was allegedly found in his carry-on bag, Anderson was charged with two felonies in U.S. District Court in Salt Lake City: Having a dangerous weapon on an aircraft and retaliation against a federal law enforcement officer by threat of murder.

His lawyer, Steve Killpack, says Anderson, who had a distinguished career at Parsons Behle & Latimer, is sorry about the incident and wants to seek treatment. He also emphasized that no one was hurt. Anderson went off medication he was taking for bipolar disorder about two years ago, according to the defense attorney, and recently also stopped taking an anti-anxiety drug.

The prosecutor in the case said this is the seventh incident involving law enforcement that Anderson has had in a little more than a year.The prior dustups allegedly included a road-rage matter in which a knife was found afterward in Anderson’s vehicle, a restaurant scuffle and an attempt to leap from a hotel balcony.

“We are very concerned that if he is released, he will pose a danger to the community,” prosecutor Michael Kennedy told Judge David Nuffer at a hearing yesterday.

It appears from a Utah Bar directory that Anderson is not currently licensed to practice.